The launch of Pay4Bugs was unique not only because it is one of the first real products launched from day one with dual stack IPv4/IPv6 access, but also because Pay4Bugs, along with its sister IPv6-enabled OpenID provider, 87id,  is the first site to make possible OpenID sign on using exclusively IPv6 in a production environment.  [...]

Aaron Toponce over at Planet Ubuntu has an excellent article with graphics that really puts the vast size of the IPv6 address space in perspective in relationship to the almost used up IPv4 address space in perspective. I would just add that 64bits of the 128bit IPv6 address space do not necessarily have to be [...]